This application claims the priority of German Patent Document 102 06 359.1-22, filed on Feb. 14, 2002, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a thermostatic valve for a coolant circuit of an internal combustion engine comprising a housing through which a flow is capable of passing and which has a first throughflow orifice for connection to a first coolant line, a second throughflow orifice for connection to a second coolant line, and a third throughflow orifice for connection to a third coolant line, a closure member which mounted in the housing and which can be adjusted by an actuating unit, the closure member having a first shut-off element for shutting off the first throughflow orifice and a second shut-off element, coupled to the first shut-off element, for shutting off the second throughflow orifice; and to a method for operating an internal combustion engine of a motor vehicle having a coolant circuit.
An aspect of the invention is to make available a particularly efficient thermostatic valve, capable of being produced in a simple way, for the cooling circuit of an internal combustion engine, a coolant circuit of an internal combustion engine, the said coolant circuit being capable of being activated particularly simply, and a method for appropriately controlling the thermostatic valve, the coolant circuit and the internal combustion engine.
This aspect may be achieved by way of a thermostatic valve—in that the second shut-off element is assigned an adjusting device via which the second shut-off element can be adjusted relative to the first shut-off element in such a way that the closure member can be brought, on one hand, into a passage position, in which the closure member can close exactly one of the throughflow orifices, and, on the other hand, into a shut-off position in which the closure member can close two of the throughflow orifice—a coolant circuit—comprising a coolant/air heat exchanger which is assigned a bypass line, coolant branching between a heat exchanger line and the bypass line being controllable as a function of temperature via a thermostatic valve which has a first connection to the heat exchanger line, a second connection to the bypass line, and a third connection to a supply or discharge line located on an internal combustion engine side and which comprises a closure member which can be adjusted by way of an actuating unit and which is assigned a first shut-off element for shutting off the heat exchanger line and a second shut-off element coupled to the first shut-off element for shutting off the bypass line, wherein the second shut-off element is assigned an adjusting device via which the second shut-off element can be adjusted relative to the first shut-off element in such a way that the closure member can be brought, on one hand, into a passage position, in which the closure member can close either the bypass line or the heat exchanger line, and, on the other hand, into a shut-off position in which the closure member can close both the bypass line and the heat exchanger line—and a method—in which, after a cold start of the internal combustion engine, the coolant circuit is initially interrupted by a thermostatic valve, and subsequently, the coolant circuit is opened between the internal combustion engine and a bypass line by an adjustment of a closure member of the thermostatic valve.
Further features and feature combinations may be gathered below and from the subclaims, the description and the drawings.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.